SQL Server 2016

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-- Create the table
CREATE TABLE df (
    country VARCHAR(50),
    year INT,
    val1 INT,
    val2 INT,
    val3 INT
);

-- Insert 10 rows of data
INSERT INTO df (country, year, val1, val2, val3) VALUES
('USA', 2020, 4, 4, 5),
  ('USA', 2020, 4, 4, 5),
  ('USA', 2020, 5, 5, 5),
  ('USA', 2020, 5, 5, 5),
  ('USA', 2020, 1, 1, 5),
  ('USA', 2020, 3, 3, 5),
  ('USA', 2020, 4, 2, 5),
  ('USA', 2020, 1, 1, 5),
  ('USA', 2020, 2, 2, 5),
  ('Canada', 2020, 1, 1, 3),
  ('Canada', 2020, 2, 2, 3),
  ('Canada', 2020, 4, 4, 3),
  ('Canada', 2020, 3, 4, 3),
  ('Canada', 2020, 3, 4, 3),
  ('Canada', 2020, 3, 4, 3),
  ('Canada', 2020, 5, 4, 3),
  ('Canada', 2020, 5, 4, 5),
  ('Canada', 2020, 5, 4, 5),
('Germany', 2022, 5, 5, 4),
('France', 2020, 1,1, 2),
  ('France', 2020, 1,1, 2),
  ('France', 2020, 3, 2, 2),
  ('France', 2020, 3, 4, 2),
  ('France', 2020, 3, 5, 5),
  ('France', 2020, 3, 4, 4),
  ('France', 2020, 3, 4, 4),
  ('France', 2020, 3, 4, 3),
('UK', 2021, 4, 2, 3),
('Australia', 2022, 3, 3, 4),
('Italy', 2020, 5, 5, 5),
  ('Italy', 2020, 5, 5, 5),
  ('Italy', 2020, 5, 1,1),
   ('Italy', 2020, 4, 4,1),
   ('Italy', 2020, 2, 1,2),
  ('Italy', 2020, 3, 5, 3),
('Spain', 2021, 1, 2, 3),
('Mexico', 2022, 4, 4, 4),
    ('Brazil', 2020, 4, 1, 1),
  ('Brazil', 2020, 4, 1, 1),
  ('Brazil', 2020, 4, 3, 4),
  ('Brazil', 2020, 5, 3, 5),
    ('Brazil', 2020, 5, 3, 5),
  ('Brazil', 2020, 3, 3, 1),
('Brazil', 2020, 2, 3, 1);
-- Add the mode column to the table
select * from df;

country	year	val1	val2	val3
USA	2020	4	4	5
USA	2020	4	4	5
USA	2020	5	5	5
USA	2020	5	5	5
USA	2020	1	1	5
USA	2020	3	3	5
USA	2020	4	2	5
USA	2020	1	1	5
USA	2020	2	2	5
Canada	2020	1	1	3
Canada	2020	2	2	3
Canada	2020	4	4	3
Canada	2020	3	4	3
Canada	2020	3	4	3
Canada	2020	3	4	3
Canada	2020	5	4	3
Canada	2020	5	4	5
Canada	2020	5	4	5
Germany	2022	5	5	4
France	2020	1	1	2
France	2020	1	1	2
France	2020	3	2	2
France	2020	3	4	2
France	2020	3	5	5
France	2020	3	4	4
France	2020	3	4	4
France	2020	3	4	3
UK	2021	4	2	3
Australia	2022	3	3	4
Italy	2020	5	5	5
Italy	2020	5	5	5
Italy	2020	5	1	1
Italy	2020	4	4	1
Italy	2020	2	1	2
Italy	2020	3	5	3
Spain	2021	1	2	3
Mexico	2022	4	4	4
Brazil	2020	4	1	1
Brazil	2020	4	1	1
Brazil	2020	4	3	4
Brazil	2020	5	3	5
Brazil	2020	5	3	5
Brazil	2020	3	3	1
Brazil	2020	2	3	1

-- Parameters
DECLARE @Year INT = 2020; --, @Country varchar(50)= 'Brazil';

WITH ModeData AS (
    SELECT country, 
           a.Mode
    FROM df
    CROSS APPLY (
        SELECT TOP 1 Mode, COUNT(*) AS cnt
        FROM (VALUES (val1), (val2), (val3)) AS t(Mode)
        GROUP BY Mode
        ORDER BY COUNT(*) DESC
    ) a
  where year=@year --and  country=@country 
)

-- Calculate proportions and map modes to labels
, Proportions AS (
    SELECT country, 
           CASE 
               WHEN Mode = 1 THEN 'Very Dissatisfied'
               WHEN Mode = 2 THEN 'Dissatisfied'
               WHEN Mode = 3 THEN 'Neutral'
               WHEN Mode = 4 THEN 'Satisfied'
               WHEN Mode = 5 THEN 'Very Satisfied'
           END AS SatisfactionLevel,
           COUNT(*) * 1.0 / SUM(COUNT(*)) OVER (PARTITION BY country) AS Proportion
    FROM ModeData
    GROUP BY country, Mode
)

-- Pivot the results to get each satisfaction level as a column
SELECT country, 
       [Very Dissatisfied], 
       [Dissatisfied], 
       [Neutral], 
       [Satisfied], 
       [Very Satisfied]
FROM Proportions
PIVOT (
    MAX(Proportion)
    FOR SatisfactionLevel IN ([Very Dissatisfied], [Dissatisfied], [Neutral], [Satisfied], [Very Satisfied])
) AS p
ORDER BY country;

country	Very Dissatisfied	Dissatisfied	Neutral	Satisfied	Very Satisfied
Brazil	0.285714285714	0.142857142857	0.142857142857	0.142857142857	0.285714285714
Canada	0.111111111111	0.111111111111	0.333333333333	0.222222222222	0.222222222222
France	0.250000000000	0.125000000000	0.250000000000	0.250000000000	0.125000000000
Italy	0.166666666666	0.166666666666	0.166666666666	0.166666666666	0.333333333333
USA	0.222222222222	0.111111111111	0.111111111111	0.333333333333	0.222222222222